1. Field of the Invention
The invention relates to a rotating turret device with a number of optical components for optical instruments, especially microscopes, it being possible for the optical components to be brought into operating position individually in each case. In the present case, optical components are taken to be, first and foremost, lenses, condensers, filters, stops, or beam-deflecting components.
2. Description of the Prior Art
Owing to increasing automation in the construction of microscopic instruments, cf., for example, microanalytical instruments or special microscopes for the semiconductor industry, motor-driven lens turrets, for example, are already known. In this connection, a desired lens is brought into operating position by means of a signal, which is generated by appropriately positioned light barriers (sensors) or contacts (microswitches). It is also already known to code lenses attached to a motor-driven microscope turret in such a way that a specified lens can be brought into operating position as desired.
Thus, there is known from German Offenlegungsschrift No. 3,240,401, for example, a rotating device which has a series of lenses of different magnifications. This known device contains encodings on the periphery of the turret, and, further, light barriers and peripheral positioning notches as well as mechanical locating means.
Moreover, the Japanese patent notification document 55-6905 already contains a description of a turret arrangement which carries a number of color filters on a rotating plate. Additionally, markings in the form of "ramps" are provided, which correspond to appropriate microswitches. The microswitches have different radial intervals from the center point of the rotating plate.
Moreover, there is known from U.S. Pat. No. 3,358,706 a device which has a rotating disc, on one side of which concentrically arranged encoding means are attached at different radial intervals. Optical means on a mount opposite the disc-namely lamps and photodiodes-cooperate with non-reflecting or reflecting encoding means.
However, all known motor-switchable turret mounts for optical components have the disadvantage that the switching time between a turret eye located in operating position and an adjacent other turret eye to be brought into operating position is relatively long. Especially with regard to a turret for microscope lenses which must be equipped with up to six and more lenses, the problem of mass means that the switch-over time from turret eye to turret eye becomes disproportionately large because of the fact that the known mechanical locating means are no longer capable of absorbing the accelerating forces which arise. For this reason, it has been necessary so far to operate with an ever slower turret speed as more equipment is added to the turret. This represents a very disadvantageous effect, which becomes especially evident in timeconsuming routine inspections.